In the commercial electrochemical process for aluminium extraction,the electrolyte used is

In the extraction process of copper,the product obtained after carrying out the reactions
$(i) 2 Cu_2S + 3 O_2 \rightarrow 2 Cu_2O + 2 SO_2$
$(ii) 2 Cu_2O + Cu_2S \rightarrow 6 Cu + SO_2$ is called

In the smelting of roasted copper pyrites ore,melting occurs so that the first reaction is:

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R).$
Assertion $(A):$ Aluminium is extracted from bauxite by the electrolysis of a molten mixture of $Al_2O_3$ with cryolite.
Reason $(R):$ The oxidation state of $Al$ in cryolite is $+3$.
In the light of the above statements,choose the most appropriate answer from the options given below:

$Al_{2}O_{3}$ was leached with alkali to get $X$. The solution of $X$ on passing of gas $Y$,forms $Z$. $X$,$Y$ and $Z$ respectively are

Which of the following is not added during the extraction of silver by the cyanide process?